Large high voltage transformers typically have tap changing mechanisms associated with primary windings of the transformer to allow primary to secondary turn ratios to be adjusted. The adjustments are typically used to compensate for variations in line voltage.
A tap changing mechanism for a transformer typically includes a series of fixed contacts. The series of fixed contacts may be connected to the taps of the primary winding of the transformer. The series of fixed contacts are typically arranged within the transformer tank and immersed in a transformer oil. A movable contact is moved between the contacts with a drive mechanism.
A size of conventional tap changing switches and a required spacing for electrical isolation within the transformer generally imposes a constraint on the minimum size of the transformer tank. Additionally, typical tap changing switches have a limited maximum operating voltage.
Accordingly, what is needed is a more compact tap changing switch that is configured to operate at higher voltages.